Heater and a heat production unit for a sauna bath



Oct. 6, 1964 P. w. SINIAHO 3,151,615

HEATER AND A HEAT PRODUCTION UNIT FOR A SAUNA BATH Filed March 11, 1963 IN VEN TOR. M afi-'dnbaio United States Patent 3,151,615 HEATER AND A HEAT PRODUCTION UNIT FOR A SAUNA BATH Paul W. Siniaho, 4549 N. 53rd Drive, Phoenix, Ariz. Filed Mar. 11, 1963, Ser. No. 264,124 Claims. (Cl. 126-364) This invention concerns a heater and a heat production unit for a sauna bath.

Heretofore and in times past steam was generated in sauna baths by heating rocks with a wood fire in an enclosed usually circular flue and then pouring water on the heated rocks. Baths of this nature are usually enclosed in a small bath house sometimes called a sauna. The walls of such building are insulated and the interiors are finished in smooth unpainted wood. It is the usual practice to locate the sauna heater in a corner of such room and to provide benches and/or shelves for the persons making use of the bath. In many Scandinavian countries these bath houses are provided with showers and in nearly all of them the sauna bath takes the place of the usual bath tubs or showers used in other countries.

One of the objects of this invention is to provide a sauna bath heater and water vaporizer which makes use of modern fuel and is combined with control apparatus so that the operation is automatic.

Another object is to provide a sauna bath having rocks contained within a tubular screen in such a way as to minimize cracking of the rocks and an accumulation of dirt from pulverized rock material.

Another object is to provide a sauna bath heater, as above referred to, which will operate efiiciently on producer or natural gas having adequate vents to prevent explosions and/ or the accumulation of unwanted materials and fibers within the sauna heater.

Still another object is to provide a sauna bath heater equipped with automatic controls which will regulate both the heat in the burner and the water supply.

It is to be understood that a bath heater of this type is intended to supply heated air, heavily saturated with water, but not containing visible steam vapor.

I attain the foregoing objects by means of the devices, parts and combinations of parts shown in the accompanying drawings, in which FIGURE 1 is a side elevational view of a sauna bath heater incorporating my improvements; and

FIGURE 2 is a vertical mid-sectional view of the device as shown in FIGURE 1.

Similar numerals refer to similar parts in the several views.

In the drawings 2 indicates a fire box in general; 3 indicates a gas burner Within the fire box; 4 indicates a vertical flue which is attached to the crown sheet 5 of the fire box at a joint indicated by numeral 6. The flue extends upward from this joint. A cylindrical jacket 7 surrounds the sides of the fire box and has an inner wall 8 and an outer wall 9. These two circular concentrically positioned walls are covered at the top by a ring cap 10.

At the top of the flue 4 there is a vent 12 which opens into an inverted funnel-like chimney transition piece 14. This is, in turn, connected to a chimney 15. Air enters the fire box through holes 16 in the bottom plate 17 of the fire box 18.

Surrounding flue 4 there is a cylindrical rock retainer 20 composed of screen sections 21. These are spaced about two inches outward from the walls of the flue and are held in place by spacer brackets 19. At intervals from the bottom of the flue there are circular funnel-like rock and water retainers 22. These are spaced at convenient intervals to allow for adequate distribution of heat on the one hand and Water distribution on the other.

3,151 ,615 Patented Oct. 6, 1964 In the device as presently illustrated there are four of these funnel-like distributors.

At the top of the flue there is a funnel-like baflle 23 which has an outer rim 24 of a larger diameter than the transition piece 14. This is intended to catch any condensation or return draft or flow from the chimney 15, and to prevent steam rising from sections 21 from going up the flue.

In the center of the flue there is a flame director and heat spreader 27 which is composed of a central rod 28 suspended on a transverse rod 29 at its top, in the top portion of flue 4. A plurality of directive vanes 30 are attached to the central rod 28 at convenient intervals to slow the up-trending draft in the flue and force the hot gases outward toward the walls of the flue.

Cleanly crushed rocks are placed in the annular spaces, such as 36, between the flue 4 and the circular screens 21. These rocks are used to absorb the water flooded over them and after being heated, evaporate it rapidly into steam. It will be noticed that there are several separated annular spaces between the several funnel-like separators 22. These rocks in spaces 21 are about the size of small walnuts. Below the bottom edge 39 of the screen 20 and in the annular space between screen 200 and the inner wall 8 of the fire box, there is an annular area which is filled with larger rocks 40 which serve the same purpose as the smaller rocks surrounding the flue except that, being larger, they retain heat longer and give up the heat to the water more slowly. Water is supplied to the top funnel-like baflle 20a from the water supply spigot 42. During operation this spigot is opened and allowed to run into the top most funnellike baflle at a rate needed to evaporate the water ethciently. The water runs from the top most funnel-like battle through a space between the lower edge 44 of the baffie and the wall 45 of the flue. Thus, the water descending from the first funnel 22 runs into the crushed rocks in a space 46 below it and above the second funnel baflle 201). There is also a space between this baflie and the next succeeding annular ring filled with crushed rock and marked 36b. The same is true of the successive rings of crushed rock below the successive spaced funnel bafiles. At the bottom of the column of crushed rock, held in position by the funnel baflles, the water drips out of and spreads into the annular ring of rocks 49 within the annular space above the fire box crown sheet and between the fire box wall 8 and the bottom portion of bottom screen 20c. In this way all water let into the top funnellike baflle 22 works its way through the spaces 36 down into the annular space above the crown sheet 5 and keeps rocks in all compartments moist sufiicient to rapidly evaporate the water taken up by said rocks. A gas burner 50 is supplied with gas under usable pressure through a pipe 51 and is safely regulated by valves contained in box 52 which valves are controlled by thermostat 53 and thermocouple 54. The main supply shutoff valve 55 connects the box 52 with the gas supply line.

In order to drain 011 any excessive water from the space above crown sheet 5 a drain pipe 56 is connected to the bottom of the annular space just above the crown sheet 5.

In use fire is started in the fire box by means used usually to start a gas burner. This burner is then regulated by the automatic means conveniently used with gas burners. The rocks mentioned above are heated by this fire. Those in the annular space immediately above the crown sheet of the fire box gain heat rapidly and those up the flue gather heat more slowly. Water is turned on from spigot 42 and allowed to run and trickle down to the smaller rocks and on into the rocks within the fire box until dissipated.

This device, when placed within the usual sauna bath house will provide heated air with a high water content and in such quantities that no further regulation except that at the fire box need be had.

To those familiar with this type of bathing it will be readily apparent it is far more efiicient to use this device supplied automatically with fuel and water and having graded and cleaned rock pieces than the old method of heating large rocks from a wood fire.

The invention is subject to many variations and details and I wish to be limited by the following claims.

I claim:

1. A sauna bath comprising a body having a cylindrical fire box at the bottom, a tubular flue extending from the top of said fire box and having means for attachment to a vent at its top, a regulatable gas burner in said fire box, a cylindrical screen surrounding said flue and defining an annular space for the retention of sized rocks, an area above said fire box providing space for rocks, funnel-like baflles attached to said cylindrical screen to provide baffles to direct water introduced into said bafiles into the area containing rocks surrounding said flue; means for supplying water to said baffles; and means for supplying gas fuel to said burner.

2. A sauna bath comprising a body having a cylindrical fire box at the bottom, a tubular flue extending from the top of said fire box and having means for attachment to a vent at its top, a regulatable gas burner in said fire box, a cylindrical screen surrounding said flue and defining an annular space for the retention of sized rocks, an annular area above said fire box providing space for rocks, a plurality of superposed spaced funnel-like baflies extending through the cylindrical screen to direct and maintain a flow of water toward said flue and over the rocks in said annular space; means for supplying water to said baflles; and means for supplying gas fuel to said burner.

3. The device as described in claim 2 wherein larger water evaporating rocks are placed in the annular area on top of said fire box, and a drain is provided at the bottom of the rock holding area surrounding said fire box.

4. In a water evaporator for a sauna bath, an evaporator comprising a central flue having a vent at the top and an opening at the bottom adapted for attachment to the crown sheet of a fire box, a fire box comprising a cylindrical wall of metal and a crown sheet at the top thereof having a central hole opening into said flue; a gas burner Within said fire box having a gas supply valve; a plurality of cylindrical screen sections surrounding said flue, inverted funnel shaped baifles extending outward from said flue between said cylindrical screen sections; sized rocks for evaporation filling the area between the flue and said cylindrical screens; a water supply pipe having a control valve and an outlet; said outlet being positioned above the uppermost cylindrical screen section; an inverted transition piece at the top of said flue, a vent pipe attached to the top of said transition piece; said uppermost funnel-like baflle being directly below said transition piece; means for thermostaticallycontrolling heat in said fire box by regulating said gas supply valve for said burner according to the temperature adjacent the lower-most screen section.

5. In the device described in claim 4, an annular area surrounding said flue and disposed above said crown sheet, sized rocks in said area to absorb heat from said crown sheet and evaporate Water received from the lowermost cylindrical screened area surrounding said flue.

References Cited in the file of this patent UNITED STATES PATENTS 536,542 Scharnweber Mar. 26, 1895 902,835 Rice Nov. 3, 1908 1,677,630 Haas et al. July 17, 1928 1,857,024 Hulme May 3, 1932 2,247,304 Mela June 24, 1941 3,022,782 Bryant Feb. 27, 1962 FOREIGN PATENTS 28,254 Finland Sept. 15, 1956 42,834 Germany May 16, 1888 639,792 Germany Dec. 12, 1936 

1. A SAUNA BATH COMPRISING A BODY HAVING A CYLINDRICAL FIRE BOX AT THE BOTTOM, A TUBULAR FLUE EXTENDING FROM THE TOP OF SAID FIRE BOX AND HAVING MEANS FOR ATTACHMENT TO A VENT AT ITS TOP, A REGULATABLE GAS BURNER IN SAID FIRE BOX, A CYLINDRICAL SCREEN SURROUNDING SAID FLUE AND DEFINING AN ANNULAR SPACE FOR THE RETENTION OF SIZED ROCKS, AN AREA ABOVE SAID FIRE BOX PROVIDING SPACE FOR ROCKS, FUNNEL-LIKE BAFFLES ATTACHED TO SAID CYLINDRICAL SCREEN TO PROVIDE BAFFLES TO DIRECT WATER INTRODUCED INTO SAID BAFFLES INTO THE AREA CONTAINING ROCKS SURROUNDING SAID FLUE; MEANS FOR SUPPLYING WATER TO SAID BAFFLES; AND MEANS FOR SUPPLYING GAS FUEL TO SAID BURNER. 